The present invention relates to an electrophoresis method, for separating and analyzing samples by electrophoresis using a capillary plate having capillary channels, in order to analyze very minute quantities of samples, such as proteins and amino acids, drugs, and the like, in the fields, such as biochemistry, molecular biology, and clinical practice.
Electrophoresis devices have been used from the past when analyzing very minute quantities of proteins and amino acids, and the like. There is a capillary electrophoresis having capillary tubes as a representative thereof. However, the handling of a device having capillary tubes is complicated. Therefore, a capillary plate having plural capillary channels formed inside a substrate has been proposed and used with the purpose of making the handling easier and also for acceleration of analysis and miniaturization of the device (see Patent Documents 1 and 2).
In the capillary plate, the capillary channels serve as separation channels for electrophoresis, and both ends are opened on the substrate surface. The openings on one end side serve as sample reservoirs for sample injection. In electrophoresis using a capillary plate (below, called also capillary electrophoresis), a separation medium is packed into the capillary channels; then samples are injected from the sample reservoirs; then a solution is injected into those reservoirs; and then voltage is applied between the two ends of the capillary channels to perform electrophoresis of the samples.
Also, it may have a process such that after packing of the separation medium into the capillary channels, the solution is injected into the reservoirs before injection of the samples, and then voltage is applied between both ends of the capillary channels to perform preprocessing.
In capillary electrophoresis, the temperature of the capillary plate itself is regulated (temperature-regulated) for improvement of its separation performance. However, the solution filled into the reservoirs during preprocessing for electrophoresis or during electrophoresis of the samples was not particularly temperature-regulated before injection. Normally, it was injected into the reservoirs in a room-temperature (normal-temperature) state, and the solution inside the sample reservoirs was temperature-regulated by temperature-regulating the capillary plate itself.
Patent Document 1: Japanese Unexamined Patent Publication No. 2002-310990
Patent Document 2: Japanese Unexamined Patent Publication No. 2003-166975
Non-Patent Document 1: Anal. Chem., 2000, 72, 3129-3137
Regardless of whether the capillary plate is temperature-regulated for improvement of separation performance, there is a phenomenon that the improvement of separation performance is not sufficiently achieved.
The present invention has been made to further improve the separation performance when performing electrophoresis by temperature-regulating the capillary plate.
Further objects and advantages of the invention will be apparent from the following description of the invention.